Dental stool or the like.



W. H. REYNOLDS.

DENTAL STOOL OR THE LIKE.

APPLICATION FILED AUG. 10, 1908.

909,223,, Patented Jan. 12, 1909.

witnesses; InventoL. 23 G MZZZZ law/$4 0M, xz m. um: flwi/ M i i TED ESTATES PATENTOFFTQE.

WILLIAM H. REYNOLDS, OF TOLEDO, OHIO, ASSIGNOR TO THE RANSOM & RANDOLPH COM- PANY, OF TOLEDO, OHIO, CORPORATION OF OHIO.

DENTAL STOOL OR Tm LIKE.

Specification of Letters Patent.

Patented Jan. 12, 1909.

Application filed August 10, 1908. Serial No. 447,799.

T 0 all whom it may concern:

Be it known that I, WILLIAM H. REY- NOLDS, a citizen of the United States, and a resident of Toledo, in the county of Lucas and State of Ohio, have invented a certain new and useful Dental Stool or the Like; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the figures of reference marked thereon, which form a part of this specification.

My invention relates to vertically adjustable stools, chairs, or the like; and has for its object the provision, in an article of this class, of a sim le and highly efficient friction clutch, wiic'h is adapted to permit a free and unrestricted raising ofthe seat rod or shaft and to efiectually lock the same in any desired position of vertical adjustment relative to the standard with which it telescopes, and which is capable of being easily and quickly released to permit a lowering of the seat-rod by gravity.

The operation, construction and arrangement of the parts of the invention are fully described in the following specification, and illustrated'in the accompanying drawings, in which,

Figure 1 is an elevation of a stool embodying my invention with the upper portion of the standardin section and the seat partially raised, and Fig. 2 is a top plan view of the clutch parts with the standard head removed i 1 Referring to the drawings, 1 designates a stool base of any suitable construction from which rises the hollow or tubular standard 2 having the head casting 3 at.

its upper end, as shown. Telescoping within the-standard 2 and head for longitudinal adjustment therein is the seat-post 4, which has the seat 5 preferably swiveled to its upper end in a suitable manner. The, head casting 3, which is longitudinally bored to receive the seat-post or rod 4, has the upper end' portion of such bore enlarged to receive the bushing 6, the inner surface of which tapers inwardly from top to bottom thereof to provide an .opening of frusto-conical shape, as shown. Mounted within the annular pocket formed between thebushing 6 and seatpost 4 are a plurality of clutch balls '7, which are intended to coact with the tapered surface of the bushing and with registering grooves 8, pro

vided longitudinally in the post surface, to frictionally resist a lowering of the seat post from a position to which it has been elevated relative to the standard. The seating of the balls, 7 is influenced by the action thereon of the spring pressed collar 9, which loosely encircles the seat-post above the balls. A coiled spring 10 yieldingly acts on said collar to hold the balls to their seat and has its outer end'thrust against a plate the balls 7 from their seat against the ten sion of the spring 10, to permit a lowering of the post 4 and its seat. The collar or sleeve 12 normally seats by gravity upon the bottom of the enlarged portion of the head bore with its upper end free from contact with the balls, and has its lower end formed with the radial flange 13, which permits a .limited longitudinal movement of the collar relative to the bushing, dueto the spacing of the'lower end of the bushingfrom the bottom of the bore by shouldering it therein or otherwise. 7

Mounted at the lower portion of the standard is a treadle 14:, which has one end projected within the standard 2 and at-.

tached to the lower end of a trip-rod 15, which is disposed within the standard at one side of the seat-post 4. The trip-rod 15 has its upper end working through a suitable bore provided in the head-casting atthe side of the seat-post and coacts at such end with the under side of the collar or sleeve 12, whereby a raising of the tripred by a lowering of the outer end of the treadle effects 2. raising or releasing movement of the collar or sleeve 12. p

It is thus apparent that in the use of a stool or chair equipped with my clutch mechanism the seat-rod 4 may be freely raised to any desired position of adjustment relative to the standard, but cannot be lowered, except when the treadle 14 is tripped, due to the clutch-balls 7 instantly cooperating with the bushing 6 to lock the seatpost against such movement as soon as the raising movement thereof ceases. 'Io lower the seat it is only necessary to depress the treadle 14, which effects a raising of the collar or sleeve 12, through the medium of the trip-rod 15, to engage and unseat the clutch 10 balls, the depression of the treadle being maintained until the seat. has lowered by gravity to the desired position.

I wish it understood that I do not desire to be restricted to the exact details of con- J5 struction and arrangement of the parts shown and described, as obvious modifications will occur to persons skilled in the art.

Having thus described my invention, what I claim as new and desire to secure by Leti ters Patent, is,

1. In combination, a standard, a seat-post telescoping within the same for relative longitudinal adjustment, a member carried by the standard and encircling the post, said member having an inner tapered surface,

clutch-balls cooperating with said member to lock the post against a lowering movement, means yieldingly acting on the balls to hold them in seated position, a collar loosely encircling the post at the lower end of said member and adapted to work upwardly therein to engage and unseat the balls to permit a lowering of the post, and manually controlled trip-means for efi'ecting an upward movement ofthe collar.

2. In combination, a hollow standard, a head carried by the standard and having a bore therethrough which is enlarged at its outer end, a seat-post working through said 40 bore and within the standard, a bushing dis-- posed within the enlarged portion ofthe head bore and havinga frusto-conical interior, balls cooperating with the interior of the bushing to prevent a lowering of the seat-post relative to the head, means yieldingly acting on the balls to normally maintain them seated, a sleeve loosely encircling the post at the base of the enlarged portion of the head bore and having its upper end 'working within the bushing, and manually controlled means for raising the sleeve relative to the bushing to engage and unseatthe balls, substantially as described.

3. In combination, a hollow standard having its head provided with a seat-post opening whichis enlar ed at its outer end, a seat-post mounted tor longitudinal adjustment in said opening and having longitudinal grooves in its surface, a plate closing the outer end of the opening around the post, a bushing secured in the enlarged end of said opening above its base and having a I frusto-conical opening therethrough, clutchballs mounted within the annular opening between the bushing and post and seating in the post grooves to prevent a lowering of the post relative to the head, a ring resting on the balls, a compression spring acting in opposition on said plate and ring to influence a seating of the balls, a sleeve mounted in the base of the enlarged portion of the CORNELL sCI-IREIBER. 

